I am thinking about switching from mint to a bsd distro. I hear that BSD unlike linux distros do not go out of date. The distro (or the bsd equivalent) i have been looking at is MidnightBSD because it can have enlightenment installed out of the box. This hasnt had a new release since 2008 though.

Is midnightBSD still up to date or is there a better bsd with enlightenment?

I don't know where you "heard" about the timeliness of the BSDs, but all of them will require updating, in order to be both supported and secure.

MidnightBSD is a pre-packaged variant of FreeBSD. The "download" page has a nearly year-old "late breaking news" statement recommending rebuilding the OS (kernel, userland) from source code after install. It would seem to me that this defeats the purpose of a pre-packaged system, as this is far more complicated than installing Enlightenment on any of the major BSDs.

Since you are looking for prepackaged systems, perhaps you should choose one that has regular updates.

...and decide for yourself which member of the *BSD family best meets your needs. None have Enlightenment configured as part of their base systems, but smart people take the time to read & understand about the package systems available in each of the *BSD's as each contains Enlightenment. Once you have the base system installed, you can have Enlightenment installed within five minutes assuming you have a reasonable Internet connection, but studying the documentation first is necessary.

So be a really smart guy. Study the documentation. Make an informed decision. You will get more out of your system by making the effort.

You can use enlightenment on any BSD distribution.
It is present in every distro.But i don`t know how much experience you have on BSDs.
The most easiest and best for beginer is OpenBSD and NetBSD.
I will recomend OpenBSD if you are a starter.I am recommending due to its packages collection which is easy to find and stable.
The most Flexible is NetBSD.You can alter this according to your needs but you must have
some expert level.
If you want to Use BSD on "as it is" basis then Use FreeBSD 8 version and install all of your required packages online.Once ready i hope you will not need to change something.
And if you are a Nix Expert then use DragonFlyBSD.

You can use enlightenment on any BSD distribution.
The most easiest and best for beginer is OpenBSD and NetBSD.
I will recomend OpenBSD if you are a starter.I am recommending due to its packages collection which is easy to find and stable.

This is new to me: I always thought OpenBSD was way more difficult ().

I would try using Fluxbox on a BSD and see how you like it compared to Englightenment. I find the minimalism a great turn on because all this extra functionality is distracting that's why I use OpenBSD with Fluxbox.